The headline, if true, would be a news story indeed: the U.S. Chamber of Commerce, according to a press release e-mailed to journalists this morning, had decided to reverse its opposition to strong climate change legislation. But that’s false. Some unknown group decided to punk the Chamber. And in the process, at least one news organization, Reuters, fell for it.

The news release, e-mailed about 11:00 a.m., linked to a “Chamber” webpage — a fake — which, in turn, featured links to official Chamber sites. The spoof page features a short National Press Club speech, purportedly by Chamber President “Tom Donahue” — his name is misspelled –, where he acknowledged that “[t]oday’s momentous decision indeed comes after a difficult period – a very long one.”

Then comes the comment from the Chamber spokesperson, one “Hingo Sembra.”

“We believe that strong climate legislation is the best way to ensure American innovation, create jobs, and make sure the U.S. and the world are on track to reduce global carbon emissions, and to provide for the needs of the American business community for generations to come.”

One interesting thing in the fake statement by the fake Chamber: Carbon taxes are still perferable to cap-and-trade legislation under consideration in Congress. “A carbon tax means less need for legislating by Congress, a surer business environment for companies, and a simpler, competition-friendly mechanism for reducing carbon than the bill’s current cap-and-trade approach,” the fake announcement read.

The Chamber’s reversal may well have been a joke. But the arguments in favor of a carbon tax are anything but a hoax.

In an amazing turn of events, the US Chamber of Commerce has changed its position and now supports action on global warming. Well, this would be true if the folks at Avaaz Action Factory had their way. The group put on a fake press conference today posing as the Chamber to draw attention to the business association’s backward looking position on climate action. The ruse worked for Reuters, which covered the “press conference” as if it was real.

It’s not yet clear who perpetrated the hoax announcing that the Chamber of Commerce had changed its position on climate change. (It hasn’t, and remains opposed to serious efforts to deal with the problem.)

But some evidence points to the Yes Men, a group of activists known for similar stunts.